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1.
Environ Sci Pollut Res Int ; 31(20): 29777-29793, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38592634

RESUMO

The toxicity of aluminum oxide (Al2O3), copper oxide (CuO), iron oxide (Fe3O4), nickel oxide (NiO), zinc oxide (ZnO), and titanium dioxide (TiO2) nanoparticles (NPs) on amphibians and their interaction with high temperatures, remain unknown. In this study, we investigated the survival, developmental, behavioral, and histological reactions of Bufotes viridis embryos and larvae exposed to different NPs for a duration of 10 days, using lethal concentrations (LC25%, LC50%, and LC75% mg/L) under both ambient (AT: 18 °C) and high (HT: 21 °C) temperatures. Based on LC, NiONPs > ZnONPs > CuONPs > Al2O3NPs > TiO2NPs > Fe3O4NPs showed the highest mortality at AT. A similar pattern was observed at HT, although mortality occurred at lower concentrations and Fe3O4NPs were more toxic than TiO2NPs. The results indicated that increasing concentrations of NPs significantly reduced hatching rates, except for TiO2NPs. Survival rates decreased, abnormality rates increased, and developmental processes slowed down, particularly for NiONPs and ZnONPs, under HT conditions. However, exposure to low concentrations of Fe3O4NPs for up to 7 days, CuONPs for up to 72 h, and NiO, ZnONPs, and TiO2NPs for up to 96 h did not have a negative impact on survival compared with the control group under AT. In behavioral tests with larvae, NPs generally induced hypoactivity at AT and hyperactivity at HT. Histological findings revealed liver and internal gill tissue lesions, and an increase in the number of melanomacrophage centers at HT. These results suggest that global warming may exacerbate the toxicity of metal oxide NPs to amphibians, emphasizing the need for further research and conservation efforts in this context.


Assuntos
Mudança Climática , Nanopartículas Metálicas , Animais , Nanopartículas Metálicas/toxicidade , Anuros , Níquel/toxicidade , Óxido de Zinco/toxicidade , Larva/efeitos dos fármacos , Titânio/toxicidade , Óxido de Alumínio/toxicidade
2.
Environ Sci Pollut Res Int ; 30(40): 92581-92593, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37493908

RESUMO

Amphibian populations are declining worldwide. These declines are caused by a variety of factors, one of which is the use of fertilizers in agriculture. This is especially true for tadpoles, which may develop in fertilizer-polluted agricultural water bodies. Nevertheless, there is little data on the toxicological consequences of fertilizers on amphibians. The goal of this study was to determine the acute and chronic toxicity of urea fertilizer on marsh frogs' (Pelophylax sp.) embryonic, larval, and metamorphic stages. For this purpose, in a static-renewal test, individuals were exposed to twelve nominal concentrations (0 to 15000 mg/L) of urea for 122 days to determine hatching success, survival, growth, development, and metamorphic traits, as well as histological consequences. Based on the results, at concentrations greater than 500 mg/L, no hatching occurred. Survivorship was unaffected for the first 72 hours, but it reached 0% on day 26 at concentrations greater than 150 mg/L. Survival and development rates decreased significantly in 100 and 150 mg/L treatments after a longer duration (day 86). Growth was reduced as well, but it was only significant at 150 mg/L. Metamorphosis time and percentage were significantly impacted, but not metamorphosis size. Increased urea fertilizer concentrations had significant histopathological consequences for the skin, gills, liver, kidneys, and striated muscles. Our results suggest that urea fertilizer, at concentrations commonly found in agroecosystems, may pose a serious threat to temperate anuran species inhabiting these conditions.


Assuntos
Fertilizantes , Ureia , Humanos , Animais , Larva , Áreas Alagadas , Anuros , Metamorfose Biológica
3.
Pathol Res Pract ; 248: 154653, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37454490

RESUMO

As one of the frequent malignancies, breast cancer (BCa) is the foremost reason for cancer-related deaths among women. The role of Human papillomavirus (HPV) in chemoresistance has rarely been investigated in previous studies. The current study sets out to the possible role of HPV in BCa chemoresistance. In this research, 90 BCa tissue and 33 normal breast tissue were collected. We evaluated the presence of the HPV genome along with the viral (E2, E6, E7) and cellular gene expression associated with cell resistance to death. Statically significant differences in the prevalence of HPV between the BCa group (25.2% or 23/90) and the control group (21.8% or 7/32) were not found. HPV-16 and HPV-18 genotypes were the abundant HPV genotypes. Resistance to the Adriamycin-Cyclophosphamide (AC), paclitaxel regimen was elevated in the HPV- group (56/70) in comparison to the HPV+ group (14/70). Nevertheless, there was no significant difference in the prevalence of resistance to AC + paclitaxel + triple-negative breast cancer combination therapy between the HPV+ group (9/20) and in the HPV- group (11/20). In the BCa group in contrast to the control group, the expression level of Bcl-2, BCL-XL, and c-IAP2 demonstrated a significant decrease, while, the expression level of cytochrome C and caspase 3 was significantly increased. This study suggests that HPV infection might contribute to BCa chemoresistance through disrupt cellular genes involved in cell death.


Assuntos
Neoplasias da Mama , Proteínas Oncogênicas Virais , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Humanos , Feminino , Papillomavirus Humano , Proteína Supressora de Tumor p53/metabolismo , Proteínas Oncogênicas Virais/genética , Citocromos c/metabolismo , Neoplasias da Mama/tratamento farmacológico , Caspase 3/metabolismo , Resistencia a Medicamentos Antineoplásicos , Papillomaviridae/genética , Paclitaxel/farmacologia , Neoplasias do Colo do Útero/patologia
4.
J Diet Suppl ; 15(2): 197-206, 2018 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-28759276

RESUMO

Nonalcoholic fatty liver disease (FLD) is a worldwide common liver disorder. Tragopogon graminifolius is used as a dietary supplement for liver disorders. This study aimed to assess the beneficial effects of a standardized preparation from T. graminifolius extract (TGE) in animal model of FLD induced by high-fat diet (HFD). The standardization of TGE based on phenolic compounds was performed using high-performance liquid chromatography (HPLC) analysis. The HFD induced metabolic and hepatic damages. TGE significantly reduced the elevations of serum triglyceride, cholesterol, low-density lipoprotein (LDL), and hepatic enzymes (p =.001 for 25, 50, and 100 mg/kg of TGE). Histopathological studies also confirmed beneficial effects of TGE in FLD. Activity of total antioxidant power, content of total thiol, myeloperoxidase (MPO) enzyme activity, and lipid peroxidation were significantly improved (p <.001). Dietary supplementation with TGE results in improvement of biochemical as well as histopathological parameters. Clinical trials are warranted to prove its efficacy and tolerability in patients with FLD.


Assuntos
Suplementos Nutricionais , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Tragopogon/química , Animais , Antioxidantes/farmacologia , Biomarcadores/sangue , Dieta Hiperlipídica , Modelos Animais de Doenças , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Ratos , Ratos Wistar
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